The Data Management, Biostatistics and Epidemiology Core will support all of the brain trauma research center projects with statistical analysis and data management. The Core has and will continue to collaborate in the design of the projects, including sample size calculation, definition of measurements and quality control. For clinical projects the Core will manage the data and perform statistical analysis. For laboratory projects the Core investigators will advise on data management and analysis and, if necessary, assist in carrying out analysis. The Core will collaborate with project investigators to prepare reports of study results. An additional responsibility will be to collaborate with other NINDS head injury centers and contribute data to a common patient database.